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United States Patent | 5,686,904 |
Bruwer | November 11, 1997 |
A method and system for the remote control of devices having a secure self learn capability. The system includes an encoder and a decoder, the encoder encoding variable information including a user key using a non-linear algorithm to produce an encoded value transmitted to the decoder, the decoder decoding the value using the same algorithm. In a learning mode a new encoder is to be added to the system. The new encoder produces an encoded value using a key generation seed. The decoder, upon receiving the encoded key generation seed, produces a decoding key based upon the decoded key generation seed. The decoding key is stored in the decoder memory allowing valid recognition of the new encoder in a secure manner.
Inventors: | Bruwer; Frederick Johannes (Montana, ZA) |
Assignee: | Microchip Technology Incorporated (Chandler, AZ) |
Appl. No.: | 313613 |
Filed: | September 30, 1994 |
Jun 21, 1994[ZA] | 94/4411 |
Current U.S. Class: | 340/5.23; 340/825.69 |
Intern'l Class: | H04Q 001/00 |
Field of Search: | 340/825.3,825.31,825.34,825.56,825.69,825.72 235/382.5 307/10.2,10.5 361/172 70/256 380/23,45,30 |
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